Determination Of Organo Phosphorus Pesticides Total-residues By Fluorescence Spectrometry And Its Alalytical Application

At present, organic phosphorus pesticide were pesticides of the biggest consumption of our country. The organic phosphorus pesticide pesticides have strong toxicity, it will cause a lot of potential danger if used in a large amount. For example, it will influence the human body health seriously, will even bring potential danger to offspring. Pesticide is used on the crops, will advance the output of the crops, and kill the weeds, the pests and the bacterium. So, one of the preventive measures in the case is to fast and accurately determine the organic phosphorus pesticide.The traditional detection methods of residues of pesticides were reported: gaseous phase chromatograms, thin layer chromatograms, Chromatogram of high-efficient liquid phase, immunoassay and biological chip etc. But some shortcomings exist in the pretreatment of the samples, such as tediousness and reagent-consuming, time-consuming. They are unable to satisfy fast and accurately determine. Compared with them, the fluorescent analytic method has some advantage: high sensitivity, few reagent, simpleness and convenience , and demonstrates its unique superiority in the field of environmental monitoring.After the fluorescence probe dyestuffs and biological macromolecule are combined, it will take on some characteristics: fluorescence characteristic, dynamics characteristic, electrochemical characteristic and gathering characteristic, etc. Based on this theory, fluorescence analytical method is acquired. The greatest strongpoint of the fluorescence probe technology is its high-level sensitivity and extremely wide dynamic response range, so it is significant to further achieve fluorescence analytical method of quantitatively determine the residual method of organic phosphorus, it will possess higher sensitivity, lower detection limit.This thesis mainly includes the content of two following respects:1. In this paper, the basic principle of the fluorescence analytic approach and the chemical foundation of organic phosphorus were summed up, organic phosphorus pesticide residue analysis some methods and the application were reviewed in details: 135 references were cited in this paper. 2. Several kinds of new fluorescence methods in determining the residuals of organic phosphorus have explored: (1) In a pH 6.2 medium of KH2PO4-Na2HPO4, the fluorescence intensity of Acridine Orange (AO) is enhanced violently when a certain concentration of the Dodecylbenzene Sulfonic Acid Sodiumsalt (SDBS) is added. The enhanced fluorescence intensity is declined obviously after adding organophosphorus pesticides and the reduced fluorescence intensity is proportional to the concentration of organophosphorus pesticides. The linear range of this assay is 0.02 ~ 0.28 mg/L and with a detection limit of 0.02 mg/L. Based on this, a new fast and simple method for the determination of the organophosphorus pesticides total-residues was developed. The method has been successfully applied to the determination of the organophosphorus pesticides total-residues in rice and soil, the recovery range was 92.1% ~ 96.8%. The relative standard deviation (RSD) range was 2.8% ~ 4.3%, which results are satisfactory. (2) In a pH = 6.0 medium of KH2PO4-Na2HPO4, the fluorescence intensity of Eosin Y is enhanced violently when a certain concentration of the Cetrimonium bromide (CTMAB) is added. The enhanced fluorescence intensity is declined obviously after adding organophosphorus pesticides and the reduced fluorescence intensity is proportional to the concentration of organophosphorus pesticides. Based on this, a new fast and simple method for the determination of the organophosphorus pesticides total-residues was developed. (3) In a pH 4.6 medium of KH2PO4-Na2HPO4, the fluorescence intensity of Neutral red(NR) is enhanced violently when a certain concentration of the Dodecylbenzene Sulfonic Acid Sodiumsalt (SDBS) is added. The enhanced fluorescence intensity is declined obviously after adding organophosphorus pesticides and the reduced fluorescence intensity is proportional to the concentration of organophosphorus pesticides. The linear range of this assay is 0.024 ~ 0.40 mg/L and with a detection limit of 0.014 mg/L. Based on this, a new fast and simple method for the determination of the organophosphorus pesticides total-residues was developed. The method has been successfully applied to the determination of the organophosphorus pesticides total-residues in flour and soil, the recovery range was 92.0 ~ 100.5%. The relative standard deviation (RSD) range was 1.08 ~ 1.81%, which results are satisfactory. (4) In the KH2PO4-Na2HPO4 (SÑ„rensen) buffer solution at pH = 6.6 , the fluorescence intensity of Titan yellow(TY) enhanced violently when a certain concentration of the Tween-80 is added. The enhanced fluorescence intensity is declined obviously after adding phoxim and the reduced fluorescence intensity is proportional to the concentration of phoxim, the linear range of this assay is 0 ~ 0.72 mg/L and the detection limit is 0.031 mg/L. Based on this, a new fast and simple method for determination of the phoxim -residues was developed.3. Study for the interaction theory between organophosphorus and fluorescence probe. The fluorescence spectra and the absorption spectra of dye, the complex of dye and organophosphorus, the complex of dye and surfactant and the complex of dye, surfactant and organophosphorus were studied. The reaction mechanisms of them were analyzed preliminarily.